IS-Y-GRAIG (IS-GRAIG), a hamlet, in the parish of LLANDDWYWAU, union of DOLGELLEY, hundred of ARDUDWY, county of MERIONETH, NORTH WALES, 4 miles (N. by W.) from Barmouth. The population is returned with the parish. It is bounded on the west by the bay of Cardigan, which here forms an irregular strand, with crags and rude precipices, extending from a chain of the Merionethshire mountains. A remarkable sand-bank, termed the Causeway, or Sam Badrig, stretches from this coast in a south-western direction, twenty-one miles into the bay, of which about nine miles are dry at low water. In several parts it is covered only to the depth of half a fathom at flood tide, but there are three breaches in it, through which vessels may pass. Some have considered it an artificial construction, and others that it formed a part of the Cantrev y Gwaelod, or the lowland hundred, which was overwhelmed by the sea at the close of the fifth century. The vulgar notion is, that it was constructed by Saint Patrick, as the name implies, who was born in this neighbourhood, at Gwaredog in Arvon, previously to his mission to Ireland. The general aspect of the hamlet, which contains the parish church, is rugged and mountainous. Agriculture and the manufacture of webs are the chief employment of the inhabitants. A small canal has been recently projetted, which will run parallel with, and at a short distance from, the coast, for the purpose of conveying the waters of two small streams to the creek near Llaa danwg church.